Video editing: keyframe values not setting
So this is a common problem and not obvious.  You need to update the keyframes after setting the value, otherwise they revert back to there former state when the timline moves.  To do this just hit the I key when hovering over the value control you want to key.

You can also use auto-keying, this is probably the behaviour you are looking for ... look for the Record symbol on the left of the transport bar.



This will automatically create a key for you for each property you change at the current position on the timeline.